[PATCH mvebu-dt] ARM: dts: turris-omnia: configure LED[2]/INTn pin as interrupt pin

[Marek Behún]

Use the `marvell,reg-init` DT property to configure the LED[2]/INTn pin
of the Marvell 88E1514 ethernet PHY on Turris Omnia into interrupt mode.

Without this the pin is by default in LED[2] mode, and the Marvell PHY
driver configures LED[2] into "On - Link, Blink - Activity" mode.

This fixes the issue where the pca9538 GPIO/interrupt controller (which
can't mask interrupts in HW) received too many interrupts and after a
time started ignoring the interrupt with error message:
  IRQ 71: nobody cared

There is a work in progress to have the Marvell PHY driver support
parsing PHY LED nodes from OF and registering the LEDs as Linux LED
class devices. Once this is done the PHY driver can also automatically
set the pin into INTn mode if it does not find LED[2] in OF.

Until then, though, we fix this via `marvell,reg-init` DT property.

Signed-off-by: Marek Behún <kabel at kernel.org>
Reported-by: Rui Salvaterra <rsalvaterra at gmail.com>
Fixes: 26ca8b52d6e1 ("ARM: dts: add support for Turris Omnia")
Cc: Uwe Kleine-König <uwe at kleine-koenig.org>
Cc: linux-arm-kernel at lists.infradead.org
Cc: Andrew Lunn <andrew at lunn.ch>
Cc: Gregory CLEMENT <gregory.clement at bootlin.com>
Cc: <stable at vger.kernel.org>

---

This patch fixes bug introduced with the commit that added Turris
Omnia's DTS (26ca8b52d6e1), but will not apply cleanly because there is
commit 8ee4a5f4f40d which changed node name and node compatible
property and this commit did not go into stable.

So either commit 8ee4a5f4f40d has also to go into stable before this, or
this patch has to be fixed a little in order to apply to 4.14+.

Please let me know how should I handle this.

---
 arch/arm/boot/dts/armada-385-turris-omnia.dts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/armada-385-turris-omnia.dts b/arch/arm/boot/dts/armada-385-turris-omnia.dts
index 646a06420c77..b0f3fd8e1429 100644
--- a/arch/arm/boot/dts/armada-385-turris-omnia.dts
+++ b/arch/arm/boot/dts/armada-385-turris-omnia.dts
@@ -389,6 +389,7 @@ &mdio {
 	phy1: ethernet-phy at 1 {
 		compatible = "ethernet-phy-ieee802.3-c22";
 		reg = <1>;
+		marvell,reg-init = <3 18 0 0x4985>;
 
 		/* irq is connected to &pcawan pin 7 */
 	};
-- 
2.26.2